1. Field of the Invention
The present invention relates to a recording tape cassette which rotatably accommodates a reel, on which recording tape is wound, in a case.
2. Description of the Related Art
A recording tape cassette which accommodates, in a case, a reel on which a recording tape such as a magnetic tape or the like is wound is employed, for example, as a recording medium for an audio device, a video device or the like. When information is to be recorded on the recording tape, or information that has been recorded on the recording tape is to be replayed, the reel is rotated and, while the recording tape is wound out or wound back, the recording tape is passed through a vicinity of (or slidingly contacted with) a recording head which is disposed in a recording/playback device such as a tape deck or the like.
The reel is structured with a reel hub and a pair of flanges. The recording tape is wound on the reel hub. The flanges are provided at both ends of the reel hub in an axial direction thereof, and restrict displacement of the recording tape in the axial direction (a width direction of the recording tape). For such a recording tape cassette, in consideration of lightness and processability, principal components, such as the case, the reel and the like, are formed by resin-molding.
In recent years, because of demands for improvements in recording capacity, reductions in thickness of recording tapes, which have conventionally had thicknesses of 13 μm or more, have been under consideration.
However, for a conventional recording tape cassette, the reel is formed by resin-molding using a general purpose resin material. Because a surface electrical resistance value of this resin material is greater than 1×1016Ω, there has been a problem in that the reel is susceptible to static charging. In consequence, when a flange of the reel slides against the case, the recording tape and the like, and the reel becomes statically charged, the recording tape that is being wound out from the reel or wound back to the reel experiences an attractive force (electrostatic attraction) to a flange side (particularly a lower flange side) thereof.
When this electrostatic attraction acts on a recording tape with a conventional thickness, strength of the tape is high and problems do not occur. However, when it is sought to make a recording tape thinner, as described above, the recording tape is drawn toward a flange of the reel by the electrostatic attraction. Thus, in a case in which a thin recording tape is employed, this electrostatic attraction is a cause of hindrance to proper running of the recording tape.